There are arguably four positions. I say arguably because I am not a fan of positions because they can be misleading. If these positions come from momentum, you are doing fine.
How do you get your arms to straighten naturally, without effort? Watch Part 2 to strengthen your understanding of Impact.
There is a way your chest, hips and hands move and a way they do not move. Here is a drill that will help you strengthen your feel for impact.
If you start the club back and the weight of the club stays towards the ball, you are doing what the pros do.